# US 12,192,488 B2 · Video encoder, video decoder, and corresponding encoding and decoding methods > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,192,488 B2 - Document ID: US12192488B2 - Status: Granted - Kind: B2 - Application number: 17/729,176 - Filed: 2022-04-26 - Published: 2022-08-18 - Granted: 2025-01-07 - Earliest claimed: 2018-07-16 - Assignees: Huawei Technologies Co., Ltd. - Applicants: Huawei Technologies Co., Ltd. - Inventors: Xiang Ma; Yin Zhao; Haitao Yang; Jianle Chen - Web page: https://patentgrep.com/patent/US12192488B2 ## CPC - H04N 19/11: among a plurality of spatial predictive coding modes - H04N 19/186: the unit being a colour or a chrominance component - H04N 19/157: Assigned coding mode, i.e. the coding mode being predefined or preselected to be further used for selection of another element or parameter - H04N 19/176: the region being a block, e.g. a macroblock - H04N 19/593: involving spatial prediction techniques - H04N: PICTORIAL COMMUNICATION, e.g. TELEVISION ## Abstract Techniques are described of a linear model prediction mode. A set of reconstructed neighboring luma samples are determined. Two pairs of luma value and chroma value are determined according to N reconstructed neighboring luma samples, N reconstructed neighboring chroma samples, M reconstructed neighboring luma samples, and M reconstructed neighboring chroma samples. The minimum value of the N reconstructed neighboring luma samples is not less than the maximum luma value of the remaining reconstructed neighboring luma samples of the set of reconstructed neighboring luma samples. The maximum value of the M reconstructed neighboring luma samples is not larger than the minimum luma value of the remaining reconstructed neighboring luma samples of the set of reconstructed neighboring luma samples. M>1 and N>1. Linear model parameters are determined based on the two pairs of luma value and chroma value, and a predictive block is determined based on the linear model parameters. ## Claims ### Claim 1 A method of decoding video data implemented by a decoding device, comprising: performing entropy decoding on a bitstream, to obtain information indicating a selected intra-prediction mode; determining a luma block that corresponds to a chroma block; determining a set of down-sampled samples of reconstructed neighboring luma samples, wherein the selected intra-prediction mode is a cross-component intra prediction_A (CCIP_A) mode, the reconstructed neighboring luma samples comprise a plurality of reconstructed luma samples that are above the luma block without including a plurality of reconstructed luma samples that are left to the luma block; determining a first pair of luma value and chroma value according to N down-sampled neighboring luma samples of the set of down-sampled samples and N reconstructed neighboring chroma samples that correspond to the N down-sampled neighboring luma samples, wherein N is a positive integer greater than 1, and a minimum luma value of the N down-sampled neighboring luma samples is not less than respective luma values of first remaining down-sampled neighboring luma samples of the set, wherein the first remaining down-sampled neighboring luma samples are different from the N down-sampled neighboring luma samples; determining a second pair of luma value and chroma value according to M down-sampled neighboring luma samples of the set of down-sampled samples and M reconstructed neighboring chroma samples that correspond to the M down-sampled neighboring luma samples, wherein M is a positive integer greater than 1, and a maximum luma value of the M down-sampled neighboring luma samples is not more than respective luma values of second remaining down-sampled neighboring luma samples of the set, wherein the second remaining down-sampled neighboring luma samples are different from the M down-sampled neighboring luma samples; deriving one or more linear model parameters based on the first pair of luma value and chroma value and the second pair of luma value and chroma value; generating a predictive block based on the one or more linear model parameters; and reconstructing the chroma block based on the predictive block. ### Claim 2 (depends on 1) The method of claim 1, wherein the set of down-sampled samples of reconstructed neighboring luma samples consists of the N down-sampled neighboring luma samples and the M down-sampled neighboring luma samples, and the sum of N and M is equal to the number of down-sampled neighboring luma samples in the set. ### Claim 3 A device of decoding video data, comprising: a memory containing programming instructions; and one or more processors in communication with the memory, wherein the one or more processors are configured to execute the programming instructions to cause the device to: perform entropy decoding on a bitstream, to obtain information indicating a selected intra-prediction mode; determine a luma block that corresponds to a chroma block; determine a set of down-sampled samples of reconstructed neighboring luma samples, wherein the selected intra-prediction mode is a cross-component intra prediction_A (CCIP_A) mode, the reconstructed neighboring luma samples comprise a plurality of reconstructed luma samples that are above the luma block without including a plurality of reconstructed luma samples that are left to the luma block; determine a first pair of luma value and chroma value according to N down-sampled neighboring luma samples of the set of down-sampled samples and N reconstructed neighboring chroma samples that correspond to the N down-sampled neighboring luma samples; wherein N is a positive integer and larger than 1, and the minimum luma value of the N down-sampled neighboring luma samples is not less than respective luma values of first remaining down-sampled neighboring luma samples of the set, wherein the first remaining down-sampled neighboring luma samples are different from the N down-sampled neighboring luma samples; determine a second pair of luma value and chroma value according to M down-sampled neighboring luma samples of the set of down-sampled samples and M reconstructed neighboring chroma samples that correspond to the M down-sampled neighboring luma samples, wherein M is a positive integer greater than 1, and the maximum luma value of the M down-sampled neighboring luma samples is not more than respective luma values of second remaining down-sampled neighboring luma samples of the set, wherein the second remaining down-sampled neighboring luma samples are different from the M down-sampled neighboring luma samples; derive one or more linear model parameters based on the first pair of luma value and chroma value and the second pair of luma value and chroma value; generate a predictive block based on the one or more linear model parameters; and reconstruct the chroma block based on the predictive block. ### Claim 4 (depends on 3) The device of claim 3, wherein the set of down-sampled samples of reconstructed neighboring luma samples consists of the N down-sampled neighboring luma samples and the M down-sampled neighboring luma samples, and the sum of N and M is equal to the number of down-sampled neighboring luma samples in the set. ### Claim 5 A non-transitory computer readable medium storing computer instructions which, when executed by a processor in a device, cause the device to perform the steps of: performing entropy decoding on a bitstream, to obtain information indicating a selected intra-prediction mode; determining a luma block that corresponds to a chroma block; determining a set of down-sampled samples of reconstructed neighboring luma samples, wherein the selected intra-prediction mode is a cross-component intra prediction_A (CCIP_A) mode, the reconstructed neighboring luma samples comprise a plurality of reconstructed luma samples that are above the luma block without including a plurality of reconstructed luma samples that are left to the luma block; determining a first pair of luma value and chroma value according to N down-sampled neighboring luma samples of the set of down-sampled samples and N reconstructed neighboring chroma samples that correspond to the N down-sampled neighboring luma samples, wherein N is a positive integer greater than 1, and a minimum luma value of the N down-sampled neighboring luma samples is not less than respective luma values of first remaining down-sampled neighboring luma samples of the set, wherein the first remaining down-sampled neighboring luma samples are different from the N down-sampled neighboring luma samples; determining a second pair of luma value and chroma value according to M down-sampled neighboring luma samples of the set of down-sampled samples and M reconstructed neighboring chroma samples that correspond to the M down-sampled neighboring luma samples, wherein M is a positive integer greater than 1, and a maximum luma value of the M down-sampled neighboring luma samples is not more than respective luma values of second remaining down-sampled neighboring luma samples of the set, wherein the second remaining down-sampled neighboring luma samples are different from the M down-sampled neighboring luma samples; deriving one or more linear model parameters based on the first pair of luma value and chroma value and the second pair of luma value and chroma value; generating a predictive block based on the one or more linear model parameters; and reconstructing the chroma block based on the predictive block. ### Claim 6 (depends on 5) The non-transitory computer readable medium of claim 5, wherein the set of down-sampled samples of reconstructed neighboring luma samples consists of the N down-sampled neighboring luma samples and the M down-sampled neighboring luma samples, and the sum of N and M is equal to the number of down-sampled neighboring luma samples in the set. ### Claim 7 (depends on 1) The method of claim 1, wherein the luma value of the first pair of luma value and chroma value is the mean luma value of the N down-sampled neighboring luma samples, and the chroma value of the first pair of luma value and chroma value is the mean chroma value of the N reconstructed neighboring chroma samples that correspond to the N down-sampled neighboring luma samples, and wherein the luma value of the second pair of luma value and chroma value is the mean luma value of the M down-sampled neighboring luma samples, and the chroma value of the second pair of luma value and chroma value is the mean chroma value of the M reconstructed neighboring chroma samples that correspond to the M down-sampled neighboring luma samples. ### Claim 8 (depends on 1) The method of claim 1, wherein M is equal to N. ### Claim 9 (depends on 8) The method of claim 8, wherein M=N=2. ### Claim 10 (depends on 1) The method of claim 1, wherein the reconstructed neighboring luma samples comprise: a top-right neighbouring luma sample outside the luma block and luma samples that are right to the top-right neighbouring luma sample outside the luma block. ### Claim 11 (depends on 1) The method of claim 1, wherein the plurality of reconstructed luma samples that are above the luma block are reconstructed neighboring luma samples adjacent to the respective top boundary. ### Claim 12 (depends on 1) The method of claim 1, wherein the reconstructed neighboring luma samples excludes luma samples that are above of a top-left neighbouring luma sample outside the luma block. ### Claim 13 (depends on 1) The method of claim 1, wherein the set of down-sampled samples of the reconstructed neighboring luma samples are obtained by down-sampling on the reconstructed neighboring luma samples. ### Claim 14 (depends on 3) The device of claim 3, wherein the luma value of the first pair of luma value and chroma value is the mean luma value of the N down-sampled neighboring luma samples, and the chroma value of the first pair of luma value and chroma value is the mean chroma value of the N reconstructed neighboring chroma samples that correspond to the N down-sampled neighboring luma samples; and wherein the luma value of the second pair of luma value and chroma value is the mean luma value of the M down-sampled neighboring luma samples, and the chroma value of the second pair of luma value and chroma value is the mean chroma value of the M reconstructed neighboring chroma samples that correspond to the M down-sampled neighboring luma samples. ### Claim 15 (depends on 3) The device of claim 3, wherein M is equal to N. ### Claim 16 (depends on 15) The device of claim 15, wherein M=N=2. ### Claim 17 (depends on 3) The device of claim 3, wherein the reconstructed neighboring luma samples comprise: a top-right neighbouring luma sample outside the luma block and luma samples that are right to the top-right neighbouring luma sample outside the luma block. ### Claim 18 (depends on 3) The device of claim 3, wherein the plurality of reconstructed luma samples that are above the luma block are reconstructed neighboring luma samples adjacent to the respective top boundary. ### Claim 19 (depends on 3) The device of claim 3, wherein the reconstructed neighboring luma samples excludes luma samples that are above of a top-left neighbouring luma sample outside the luma block. ### Claim 20 (depends on 3) The device of claim 3, wherein the set of down-sampled samples of the reconstructed neighboring luma samples are obtained by down-sampling on the reconstructed neighboring luma samples.